The Curiosity Rover on Mars has detected what's been called a "whiff of methane" on Mars. Cue the laughter. Do you think it's a Martian cow, or a six-year-old, who's still giggling about farting on the alien RC Car roaming around the planet?

“We have full confidence that there is methane in the atmosphere of Mars,” announced John Grotzinger of CalTech, a Curiosity project scientist, on December 16. “Life is one of the few hypotheses for the formation of methane on Mars”.